The performance expectation above was developed using the following elements from A Framework for K-12 Science Education: Disciplinary Core Ideas

Transcription

1 HS-ESS1-1 HS-ESS1-1. Develop a model based on evidence to illustrate the life span of the sun and the role of nuclear fusion in the sun s core to release energy in the form of radiation. [Clarification Statement: Emphasis is on the energy transfer mechanisms that allow energy from nuclear fusion in the sun s core to reach Earth. Examples of evidence for the model include observations of the masses and lifetimes of other stars, as well as the ways that the sun s radiation varies due to sudden solar flares ( space weather ), the 11-year sunspot cycle, and non-cyclic variations over centuries.] [Assessment Boundary: Assessment does not include details of the atomic and sub-atomic processes involved with the sun s nuclear fusion.] Developing and Using Models Modeling in 9 12 builds on K 8 experiences and progresses to using, synthesizing, and developing models to predict and show relationships among variables between systems and their components in the natural and designed world(s). Develop a model based on evidence to illustrate the relationships between systems or between components of a system. ESS1.A: The Universe and Its Stars The star called the sun is changing and will burn out over a lifespan of approximately 10 billion years. PS3.D: Energy in Chemical Processes and Everyday Life Nuclear fusion processes in the center of the sun release the energy that ultimately reaches Earth as radiation. (secondary) Scale, Proportion, and Quantity The significance of a phenomenon is dependent on the scale, proportion, and quantity at which it occurs. Observable features of the student performance by the end of the course: 1 Components of the model a Students use evidence to develop a model in which they identify and describe* the relevant components, including: i. Hydrogen as the sun s fuel; ii. Helium and energy as the products of fusion processes in the sun; and iii. That the sun, like all stars, has a life span based primarily on its initial mass, and that the sun s lifespan is about 10 billion years. 2 Relationships a In the model, students describe* relationships between the components, including a description* of the process of radiation, and how energy released by the sun reaches Earth s system. 3 Connections a Students use the model to predict how the relative proportions of hydrogen to helium change as the sun ages. b Students use the model to qualitatively describe* the scale of the energy released by the fusion process as being much larger than the scale of the energy released by chemical processes. c Students use the model to explicitly identify that chemical processes are unable to produce the amount of energy flowing out of the sun over long periods of time, thus requiring fusion processes as the mechanism for energy release in the sun. June 2015 Page 1 of 10

2 HS-ESS1-2 HS-ESS1-2. Construct an explanation of the Big Bang theory based on astronomical evidence of light spectra, motion of distant galaxies, and composition of matter in the universe. [Clarification Statement: Emphasis is on the astronomical evidence of the red shift of light from galaxies as an indication that the universe is currently expanding, the cosmic microwave background as the remnant radiation from the Big Bang, and the observed composition of ordinary matter of the universe, primarily found in stars and interstellar gases (from the spectra of electromagnetic radiation from stars), which matches that predicted by the Big Bang theory (3/4 hydrogen and 1/4 helium).] Constructing Explanations and Designing Solutions Constructing explanations and designing solutions in 9 12 builds on K 8 experiences and progresses to explanations and designs that are supported by multiple and independent student-generated sources of evidence consistent with scientific ideas, principles, and theories. Construct an explanation based on valid and reliable evidence obtained from a variety of sources (including students own investigations, theories, simulations, peer review) and the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future Connections to Nature of Science Science Models, Laws, Mechanisms, and Theories Explain Natural Phenomena A scientific theory is a substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment and the science community validates each theory before it is accepted. If new evidence is discovered that the theory does not accommodate, the theory is generally modified in light of this new evidence. ESS1.A: The Universe and Its Stars The study of stars light spectra and brightness is used to identify compositional elements of stars, their movements, and their distances from Earth. The Big Bang theory is supported by observations of distant galaxies receding from our own, of the measured composition of stars and nonstellar gases, and of the maps of spectra of the primordial radiation (cosmic microwave background) that still fills the universe. Other than the hydrogen and helium formed at the time of the Big Bang, nuclear fusion within stars produces all atomic nuclei lighter than and including iron, and the process releases electromagnetic energy. Heavier elements are produced when certain massive stars achieve a supernova stage and explode. PS4.B: Electromagnetic Radiation Atoms of each element emit and absorb characteristic frequencies of light. These characteristics allow identification of the presence of an element, even in microscopic quantities. (secondary) Energy and Matter Energy cannot be created or destroyed only moved between one place and another place, between objects and/or fields, or between systems Connections to Engineering, Technology, and Applications of Science Interdependence of Science, Engineering, and Technology Science and engineering complement each other in the cycle known as research and development (R&D). Many R&D projects may involve scientists, engineers, and others with wide ranges of expertise Connections to Nature of Science Scientific Knowledge Assumes an Order and Consistency in Natural Systems Scientific knowledge is based on the assumption that natural laws operate today as they did in the past and they will continue to do so in the future. Science assumes the universe is a vast single system in which basic laws are consistent. June 2015 Page 2 of 10

3 Observable features of the student performance by the end of the course: 1 Articulating the explanation of phenomena a Students construct an explanation that includes a description* of how astronomical evidence from numerous sources is used collectively to support the Big Bang theory, which states that the universe is expanding and that thus it was hotter and denser in the past, and that the entire visible universe emerged from a very tiny region and expanded. 2 Evidence a Students identify and describe* the evidence to construct the explanation, including: i. The composition (hydrogen, helium and heavier elements) of stars; ii. The hydrogen-helium ratio of stars and interstellar gases; iii. The redshift of the majority of galaxies and the redshift vs. distance relationship; and iv. The existence of cosmic background radiation. b Students use a variety of valid and reliable sources for the evidence, which may include students own investigations, theories, simulations, and peer review. c Students describe* the source of the evidence and the technology used to obtain that evidence. 3 Reasoning a Students use reasoning to connect evidence, along with the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future, to construct the explanation for the early universe (the Big Bang theory). Students describe* the following chain of reasoning for their explanation: i. Redshifts indicate that an object is moving away from the observer, thus the observed redshift for most galaxies and the redshift vs. distance relationship is evidence that the universe is expanding. ii. The observed background cosmic radiation and the ratio of hydrogen to helium have been shown to be consistent with a universe that was very dense and hot a long time ago and that evolved through different stages as it expanded and cooled (e.g., the formation of nuclei from colliding protons and neutrons predicts the hydrogen-helium ratio [numbers not expected from students], later formation of atoms from nuclei plus electrons, background radiation was a relic from that time). iii. An expanding universe must have been smaller in the past and can be extrapolated back in time to a tiny size from which it expanded. June 2015 Page 3 of 10

4 HS-ESS1-3 HS-ESS1-3. Communicate scientific ideas about the way stars, over their life cycle, produce elements. [Clarification Statement: Emphasis is on the way nucleosynthesis, and therefore the different elements created, varies as a function of the mass of a star and the stage of its lifetime.] [Assessment Boundary: Details of the many different nucleosynthesis pathways for stars of differing masses are not assessed.] Obtaining, Evaluating, and Communicating Information Obtaining, evaluating, and communicating information in 9 12 builds on K 8 experiences and progresses to evaluating the validity and reliability of the claims, methods, and designs. Communicate scientific ideas (e.g., about phenomena and/or the process of development and the design and performance of a proposed process or system) in multiple formats (including orally, graphically, textually, and mathematically). ESS1.A: The Universe and Its Stars The study of stars light spectra and brightness is used to identify compositional elements of stars, their movements, and their distances from Earth. Other than the hydrogen and helium formed at the time of the Big Bang, nuclear fusion within stars produces all atomic nuclei lighter than and including iron, and the process releases electromagnetic energy. Heavier elements are produced when certain massive stars achieve a supernova stage and explode. Energy and Matter In nuclear processes, atoms are not conserved, but the total number of protons plus neutrons is conserved. Observable features of the student performance by the end of the course: 1 Communication style and format a Students use at least two different formats (e.g., oral, graphical, textual, and mathematical) to communicate scientific information, and cite the origin of the information as appropriate. 2 Connecting the DCIs and the CCCs a Students identify and communicate the relationships between the life cycle of the stars, the production of elements, and the conservation of the number of protons plus neutrons in stars. Students identify that atoms are not conserved in nuclear fusion, but the total number of protons plus neutrons is conserved. b Students describe* that: i. Helium and a small amount of other light nuclei (i.e., up to lithium) were formed from high-energy collisions starting from protons and neutrons in the early universe before any stars existed. ii. More massive elements, up to iron, are produced in the cores of stars by a chain of processes of nuclear fusion, which also releases energy. iii. Supernova explosions of massive stars are the mechanism by which elements more massive than iron are produced. iv. There is a correlation between a star s mass and stage of development and the types of elements it can create during its lifetime. v. Electromagnetic emission and absorption spectra are used to determine a star s composition, motion and distance to Earth. June 2015 Page 4 of 10

5 HS-ESS1-4 HS-ESS1-4. Use mathematical or computational representations to predict the motion of orbiting objects in the solar system. [Clarification Statement: Emphasis is on Newtonian gravitational laws governing orbital motions, which apply to human-made satellites as well as planets and moons.] [Assessment Boundary: Mathematical representations for the gravitational attraction of bodies and Kepler s laws of orbital motions should not deal with more than two bodies, nor involve calculus.] Using Mathematical and Computational Thinking Mathematical and computational thinking in 9 12 builds on K 8 experiences and progresses to using algebraic thinking and analysis, a range of linear and nonlinear functions including trigonometric functions, exponentials and logarithms, and computational tools for statistical analysis to analyze, represent, and model data. Simple computational simulations are created and used based on mathematical models of basic assumptions. Use mathematical or computational representations of phenomena to describe explanations. ESS1.B: Earth and the Solar System Kepler s laws describe common features of the motions of orbiting objects, including their elliptical paths around the sun. Orbits may change due to the gravitational effects from, or collisions with, other objects in the solar system. Scale, Proportion, and Quantity Algebraic thinking is used to examine scientific data and predict the effect of a change in one variable on another (e.g., linear growth vs. exponential growth) Connections to Engineering, Technology, and Applications of Science Interdependence of Science, Engineering, and Technology Science and engineering complement each other in the cycle known as research and development (R&D). Many R&D projects may involve scientists, engineers, and others with wide ranges of expertise. Observable features of the student performance by the end of the course: 1 Representation a Students identify and describe* the following relevant components in the given mathematical or computational representations of orbital motion: the trajectories of orbiting bodies, including planets, moons, or human-made spacecraft; each of which depicts a revolving body s eccentricity e = f/d, where f is the distance between foci of an ellipse, and d is the ellipse s major axis length (Kepler s first law of planetary motion). 2 Mathematical or computational modeling a Students use the given mathematical or computational representations of orbital motion to depict that the square of a revolving body s period of revolution is proportional to the cube of its distance to a gravitational center (T 2 R 3, where T is the orbital period and R is the semimajor axis of the orbit Kepler s third law of planetary motion). 3 Analysis a Students use the given mathematical or computational representation of Kepler s second law of planetary motion (an orbiting body sweeps out equal areas in equal time) to predict the relationship between the distance between an orbiting body and its star, and the object s orbital velocity (i.e., that the closer an orbiting body is to a star, the larger its orbital velocity will be). June 2015 Page 5 of 10

6 b c Students use the given mathematical or computational representation of Kepler s third law of planetary motion (T 2 R 3, where T is the orbital period and R is the semi-major axis of the orbit) to predict how either the orbital distance or orbital period changes given a change in the other variable. Students use Newton s law of gravitation plus his third law of motion to predict how the acceleration of a planet towards the sun varies with its distance from the sun, and to argue qualitatively about how this relates to the observed orbits. June 2015 Page 6 of 10

7 HS-ESS1-5 HS-ESS1-5. Evaluate evidence of the past and current movements of continental and oceanic crust and the theory of plate tectonics to explain the ages of crustal rocks. [Clarification Statement: Emphasis is on the ability of plate tectonics to explain the ages of crustal rocks. Examples include evidence of the ages of oceanic crust increasing with distance from mid-ocean ridges (a result of plate spreading) and the ages of North American continental crust decreasing with distance away from a central ancient core of the continental plate (a result of past plate interactions).] Engaging in Argument from Evidence Engaging in argument from evidence in 9 12 builds on K 8 experiences and progresses to using appropriate and sufficient evidence and scientific reasoning to defend and critique claims and explanations about the natural and designed world(s). Arguments may also come from current scientific or historical episodes in science. Evaluate evidence behind currently accepted explanations or solutions to determine the merits of arguments. ESS1.C: The History of Planet Earth Continental rocks, which can be older than 4 billion years, are generally much older than the rocks of the ocean floor, which are less than 200 million years old. ESS2.B: Plate Tectonics and Large-Scale System Interactions Plate tectonics is the unifying theory that explains the past and current movements of the rocks at Earth s surface and provides a framework for understanding its geologic history. (ESS2.B Grade 8 GBE) (secondary) PS1.C: Nuclear Processes Spontaneous radioactive decays follow a characteristic exponential decay law. Nuclear lifetimes allow radiometric dating to be used to determine the ages of rocks and other materials. (secondary) Patterns Empirical evidence is needed to identify patterns. Observable features of the student performance by the end of the course: 1 Identifying the given explanation and the supporting evidence a Students identify the given explanation, which includes the following idea: that crustal materials of different ages are arranged on Earth s surface in a pattern that can be attributed to plate tectonic activity and formation of new rocks from magma rising where plates are moving apart. b Students identify the given evidence to be evaluated. 2 Identifying any potential additional evidence that is relevant to the evaluation a Students identify and describe* additional relevant evidence (in the form of data, information, models, or other appropriate forms) that was not provided but is relevant to the explanation and to evaluating the given evidence, including: i. Measurement of the ratio of parent to daughter atoms produced during radioactive decay as a means for determining the ages of rocks; ii. Ages and locations of continental rocks; iii. Ages and locations of rocks found on opposite sides of mid-ocean ridges; and June 2015 Page 7 of 10

8 iv. The type and location of plate boundaries relative to the type, age, and location of crustal rocks. 3 Evaluating and critiquing a Students use their additional evidence to assess and evaluate the validity of the given evidence. b Students evaluate the reliability, strengths, and weaknesses of the given evidence along with its ability to support logical and reasonable arguments about the motion of crustal plates. 4 Reasoning/synthesis a Students describe* how the following patterns observed from the evidence support the explanation about the ages of crustal rocks: i. The pattern of the continental crust being older than the oceanic crust; ii. The pattern that the oldest continental rocks are located at the center of continents, with the ages decreasing from their centers to their margin; and iii. The pattern that the ages of oceanic crust are greatest nearest the continents and decrease in age with proximity to the mid-ocean ridges. b Students synthesize the relevant evidence to describe* the relationship between the motion of continental plates and the patterns in the ages of crustal rocks, including that: i. At boundaries where plates are moving apart, such as mid-ocean ridges, material from the interior of the Earth must be emerging and forming new rocks with the youngest ages. ii. The regions furthest from the plate boundaries (continental centers) will have the oldest rocks because new crust is added to the edge of continents at places where plates are coming together, such as subduction zones. iii. The oldest crustal rocks are found on the continents because oceanic crust is constantly being destroyed at places where plates are coming together, such as subduction zones. June 2015 Page 8 of 10

9 HS-ESS1-6 HS-ESS1-6. Apply scientific reasoning and evidence from ancient Earth materials, meteorites, and other planetary surfaces to construct an account of Earth s formation and early history. [Clarification Statement: Emphasis is on using available evidence within the solar system to reconstruct the early history of Earth, which formed along with the rest of the solar system 4.6 billion years ago. Examples of evidence include the absolute ages of ancient materials (obtained by radiometric dating of meteorites, moon rocks, and Earth s oldest minerals), the sizes and compositions of solar system objects, and the impact cratering record of planetary surfaces.] Constructing Explanations and Designing Solutions Constructing explanations and designing solutions in 9 12 builds on K 8 experiences and progresses to explanations and designs that are supported by multiple and independent student-generated sources of evidence consistent with scientific ideas, principles, and theories. Apply scientific reasoning to link evidence to the claims to assess the extent to which the reasoning and data support the explanation or conclusion Connections to Nature of Science Science Models, Laws, Mechanisms, and Theories Explain Natural Phenomena A scientific theory is a substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment, and the science community validates each theory before it is accepted. If new evidence is discovered that the theory does not accommodate, the theory is generally modified in light of this new evidence. Models, mechanisms, and explanations collectively serve as tools in the development of a scientific theory. ESS1.C: The History of Planet Earth Although active geologic processes, such as plate tectonics and erosion, have destroyed or altered most of the very early rock record on Earth, other objects in the solar system, such as lunar rocks, asteroids, and meteorites, have changed little over billions of years. Studying these objects can provide information about Earth s formation and early history. PS1.C: Nuclear Processes Spontaneous radioactive decays follow a characteristic exponential decay law. Nuclear lifetimes allow radiometric dating to be used to determine the ages of rocks and other materials. (secondary) Stability and Change Much of science deals with constructing explanations of how things change and how they remain stable. Observable features of the student performance by the end of the course: 1 Articulating the explanation of phenomena a Students construct an account of Earth s formation and early history that includes that: i. Earth formed along with the rest of the solar system 4.6 billion years ago. ii. The early Earth was bombarded by impacts just as other objects in the solar system were bombarded. iii. Erosion and plate tectonics on Earth have destroyed much of the evidence of this bombardment, explaining the relative scarcity of impact craters on Earth. June 2015 Page 9 of 10

10 2 Evidence a Students include and describe* the following evidence in their explanatory account: i. The age and composition of Earth s oldest rocks, lunar rocks, and meteorites as determined by radiometric dating; ii. The composition of solar system objects; iii. Observations of the size and distribution of impact craters on the surface of Earth and on the surfaces of solar system objects (e.g., the moon, Mercury, and Mars); and iv. The activity of plate tectonic processes, such as volcanism, and surface processes, such as erosion, operating on Earth. 3 Reasoning a Students use reasoning to connect the evidence to construct the explanation of Earth s formation and early history, including that: i. Radiometric ages of lunar rocks, meteorites and the oldest Earth rocks point to an origin of the solar system 4.6 billion years ago, with the creation of a solid Earth crust about 4.4 billion years ago. ii. Other planetary surfaces and their patterns of impact cratering can be used to infer that Earth had many impact craters early in its history. iii. The relative lack of impact craters and the age of most rocks on Earth compared to other bodies in the solar system can be attributed to processes such as volcanism, plate tectonics, and erosion that have reshaped Earth s surface, and that this is why most of Earth s rocks are much younger than Earth itself. June 2015 Page 10 of 10